Electrostatic generator



July 24, 1956 N. FELICI ET AL ELECTROSTATIC GENERATOR 4 Sheets-Sheet 1 Filed Sept. 21, 1955 Marcel Pofn't Y Q 1 K m m ATTORNEY INVENTQRS NO' F ellu July 24, 1956 N. FELICI ET AL ELECTROSTATIC GENERATOR Filed Sept. 21, 1955 4 Sheets-Sheet 3 ATTORNEY July 24, 1956 N. FELICI ET AL ELECTROSTATIC GENERATOR 4 Sheets-Sheet 4 Filed Sept. 21, 1955 I. WW

INVENTORS N091 Fell C q rcel Paint ATTORNEY United States Patent Office ELECTROSTATIC GENERATOR Noel Felici and Marcel Point, Grenoble (Isere), France,

assignors to Societe Anonyme de Machines Electrostatiques, Grenoble, France, a corporation of France Continuation of application Serial No. 258,343, November 27, 1951. This application September 21, 1955, Serial No. 535,722

Claims priority, application France November 29, 1950 Claims. (Cl. 310--6) The present invention concerns the supply of short current impulses of very high voltage.

Such pulses are necessary in a number of electro-technical applications in which considerable energy must be developed and utilized in a very short time, in some applications at predetermined instants and with a high timing accuracy.

This necessity occurs, for instance, in the electrical ignition of internal combustion engines, the production of electro-magnetic wave trains for detecting purposes, range finding of objects by an echo method, the production of physico-chemical reactions involving effects of a purely electric or magnetic nature without any undesirable increase of the ambient temperature, and other similar cases.

As regards more particularly ignition in internal combustion engines, it has already been proposed in the patent to Felici 2,590,168, March 25, 1952, to substitute for a discharge resulting from high voltage of inductive origin a purely capacitive discharge obtained by means of a circuit comprising a condenser capable of being charged periodically at a high voltage, a distributor having a rotating finger connected with one of the terminals of the condenser and capable of passing successively opposite to and at spark gap distance from stationary electrodes respectively connected with one electrode of the respective spark plugs of the engine, the other electrodes of these spark plugs and the other terminal of the condenser being grounded, the distributor being enclosed inside an air tight casing filled with pressurized gas. The condenser is discharged at each passage of the distributor finger opposite a stationary electrode across the interval between this finger and such stationary electrode in the circuit con taining the spark plug corresponding to this stationary electrode, the ignition spark then taking place between the electrodes of said spark plug. The condenser then is charged anew before the finger passes opposite the next stationary electrode.

It has also been proposed in the Patent 2,590,168 to use for charging the condenser a high voltage electrostatic generator and, further, to use as a condenser for causing the discharge the electrodes themselves-inductor members and conveyor members-of an influence type electrostatic generator with conducting conveyor members.

The considerable advantages obtained with a purely capacitive discharge as compared with an inductive discharge for the ignition of internal combustion engines are already known. These advantages, the more important of which are that the quality of the spark is not influenced by the rotation speed of the engine, the steadiness of the ignition point, the possibility of shielding the ignition circuit and of obtaining good ignition even if the spark plugs are dirty or if their insulation is poor, as Well as decreased wear of the spark plugs, result mainly from the very high concentration of the energy causing each discharge and from the fact that the ignition point or 2,756,352 Fatentetl July 24, 19553 instant is not determined by an interrupter, as in the coil and magneto systems, but by the distributor itself.

The object of the present invention is the provision of an electrostatic generator capable of generating very short current impulses at a very high voltage and capable of being used in a particularly convenient manner for ignition in internal combustion engines. This generator can also be used in all applications, such as those noted above, where impulses of the above mentioned type must be available.

The generator of the invention comprises, fundamentally, a pair of inductor members and preferably a plurality of pairs of inductor members arranged in two groups with the inductor members of one group insulated from those of the other group. The inductor members of the respective pairs in each group, that is, all the inductors of a group, are maintained at the same potential, the potentials of the two groups preferably being symmetrical with respect to an intermediate reference potential, for instance ground potential. To this end the inductor members of the respective groups may be connected to two sources of electrical potential difference. Respective terminals of these sources may be at the symmetrical potentials referred to, the other terminals both being connected to the reference potential.

The inductor members may be arranged symmetrically about the axis of a common shaft in such a manner that each inductor member of one group is disposed between two inductor members of the other group. A conveyor, and preferably at least one pair of conveyor members, for carrying the electrostatic charges is arranged symmetrically on a rotor rotating with the common shaft, the angular spacing about the shaft axis of these conveyor members being substantially equal to that of the inductors of like potential. The conveyors and inductors are arraged for movement of the conveyors into and out of inductive relation in succession alternately to the inductors of symmetrical potential as the shaft is rotated.

The conveyor members are connected with a conductive element or elements, a finger or fingers, supported on the rotor for rotation therewith and movable in such rotation into and out of successive positions at spark gap distance from the electrodes of as many pairs of fixed electrodes as there are pairs of inductor members distributed'about the shaft axis. These electrodes are connected respectively with one of the terminals of a utilization circuit or circuits the other terminal of which may be connected to the reference potential above referred to, for example the ground. The rotary fingers and fixed electrodes are arranged in such a manner that a finger comes into registry with a fixed electrode When the conveyor member or members connected to this finger are in the position of maximum capacity with respect to the inductor member corresponding to this electrode. All of the inductors and conveyor members together with the moving fingers and fixed electrodes preferably are enclosed in a casing capable of confining theerin a gas under pressure.

The sources of electrical potential capable of raising the two groups of inductor members to symmetrical potentials are conveniently constituted by auxiliary electrostatic generator machines. These machines may be arranged on the same shaft as the main generator machine which generates the short current impulses and may operate within the same enclosure as the main generator machine. However, since in practice the voltage-current characteristics of these two exciters are of the series type, the potential will have a tendency to rise up to the breakdown value of the gas dielectric between the electrodes. In order to hold the two voltages of the two groups of inductors respectively supplied from the two auxiliary or exciter electrostatic generators' constant'andsymmetrical, a voltage limiter is provided and -mayconsist, for' instance; inproviding" a" grounded element into register with which a spark gap distance the fingers or other charge conductive means connected withthe respective'excitatibn conveyors move, each" spark gapacting during the period" whenthe eitciteficon ve yor pot'ential increases, i. e. th'e'spa'rk' gap isdispbSed circumferentially between that exciter brush "or collector whichis groundedand that exci'ter brush or collector tiorr ge'nerators "is divided; in the direction of restarted of' titemachiney into-segments insulatdfrom' one" another, the charge conductive means servin as finger? cor responding to the conveyor'thusdivided into segrrientsit selfbe'ingfdiyid'e'd'into as man "secrorsinsniatea rom one another as there are segments iirthe conveyor member, each conveyor member segment b eingconhectd with'a sector. A spark gap'is arranged, in relation to thedireetionof r'otation'of the ma hine; ahead of reach oneof th' e' brushes orcollec'tors which cooperate with'the sectors" to place them in' connection witha'n' inductor of the main generator, this spark g'ap'being arranged so that the sectors pass at a predeterinined spark g-ap distance" from-a" grou'nded element" to discharge through th'is' sparkgap before these'c'toris connected to thebrush which isconnectedto the main'inductorif' the potential of' thesector is" excessive.

The invention is describ'ediri' greater detail hereinafter with reference to the appended drawings wherein:

Fig. l" is a diagrammatic view, in perspective, of a generator" inaccor dancewith the invention" for the ignition ofatom-cylinder, four-stroke, internal combustion engine;

Fig; 2 is" an assembly of three diagrams illustrating the operation'of said generator in three successive positions, a, b 'afidc.

Fig; 3 is a' view, partly in longitudinalsection, partly in elevation, of a practical type of embodiment of a generator for ignition of' a single cylinder engine with a simultaneous do'ub'le' ignition.

Fig. 4 is a diagrammatic view, in section alongline IVIV in Fig. 3, with an indication of the electrical connections; I

Fig." 5 is a similar view, in section, along line V'--V in Fig! 3. v I, V

Fig} 6 is' a partialdiagram of a modified embodiment of theg'en'era'tor of Fig. 1, illustrating, in addition,.the' arra gernentfor limitingthe potential fluctuations" of the indii c'tofs byfmeans o f the voltage limiter.

As"represehted' in Fig. l, the generator according to the invention" comprises two pairs of inductor members 1, 1' and" 2, 2", consisting of cylindrical segments arranged symmetrically about an axis XX, the inductorsof each pair being diametrally opposite to each other. The inductors 1, 1 forming one pair are electrically connected together and to the negative terminal of a direct currerit'supply 3, the otherterminal of which is groundedand in which the potential ditference across the terminals is equal to U. Similarly, the inductors-2, 2' forming'th'e other pair are electrically connected together and to the positive terminal of a direct current supply 4 the other terminal of which is grounded and inwhich the potential difference across the terminals is also equal to'U. With the inductors 1, 1', 2;, 2-, cooperate two conveyorme'rnber's 5 and 5' carried on a rotor 5a of insulatingmaterial arranged on a shaft 5b rotatable on the axis XX'. This shaftmay be mechanically connected with the shaft of an internal combustion engine through a mechanism, knownper se, notshown. The con 4', veyors 5 and 5' are electrically connected together through 'a conductor6"towhich' is electrically connected a distributing finger 7 supported upon and for rotation with the rotor 5a.

Around the trajectory of theend of finger 7 are arranged four stationary electrodes represented diagrammatically at 8, 8' 8" and Sdistributed-syrntnetrically, in such a manner that the finger 7 comes opposite to and rat" ashort dis tan'ce from one of "the electrodes whenathe capacity between- -the conveyors 5, 5" and one of.-the inductor pairs 1, 1, or 2, 2 passes through its maximum. These electrodes 8, 8', 8' 8 areconnected respec= tively wit-h one of the electrodesof the A respective-ispjark plug in the engine the other electrode of which is grounded, a-single one of -thespark plugs' being: shown diagrammatically at 9.

The assembly of the'inductors', conveyors and electrodes 8, 8, 8 and 8" may be enclosed within sealed enclosure containing, for instance, air under a pressure of 20 atmospheres.

The device thus constituted operates as follows:

In the position a, Fig. 2, representing the-first operating" phase, the conveyors'5 and 5' which are respectively; opposite the inductors 1 and 1 raised to the potentialv -U by the source 3, Fig. 1,- provide with these inductors a niaximumcapacity, C and the distributingnfingeri 7 is opposite'the fixed' 'electrode 8: Two sparks take place; that is, between the finger 7 and the fixed electrode8, on the one hand, and'between the'electrodes of the spark plugf9, o'h'th'e other handl As the resistance of theispark' is low the conveyors 5; 5" areeffectively grounded,- throiiglith'e' circuit thus set up. The potential V of the conveyors is thencloseto-Zero and the conveyors assume a charge +CU.

Theconveyors 5, 5 are then rotated from positionza facin'g'theinductors 1, l'toward the position facing the inductors" 2; 2 maintained at the. potential +U by the supply 4, position b', Fig. 2. During this displacement. the potential V'of the conveyors increases.

Continuing their displacement, the conveyors 5, 5 reach thep'osition fully facing the inductors 2, 2,.position'c; Fig. 2, in which their capacity with respect to the induCto'r'sZ', 2 is a maximum and equal-to C and-for which position the distributing finger 7 comes opposite the fixedelectro'de 8. Sparks are then initiatedbetween the'fin'ger 7and'the fixed electrode 8' and between the electrodes of the sparkplug The conveyors lose-their ch'arge"+CU and beingopposite inductors 2, 2' at 3.1130- tential- +U take on a charge CU through. thecircuit closed byspa'rks. The totalcharge transferred is thus eqti'al'to' ZCU The cycle is'then continued in asymmetrical: manner whenth'econveyors 5 and 5' come again under the-. inductorsl and"? with this difierence, with respect to-the initial phase" a, that when the finger 7 comes opposite the electrode 8 there will flow in-the circuit cotnprisingg the spark plug 9" corresponding thereto a: charge 2CU' as in theabovedescribed'phase c. p

In" the case just described, the mechanical. connection. between the engine shaft and the shaft of the generator is such'that'thelatter rotates one revolution for every twdfevolutions' of the engine shaft.

In practice, the sources of potential dilference 3 and 4 conveniently may consist of exciter electrostatic generat'o'rs keyed o'n the' shaft 5b and opera-tingin the same enclosure as the main generator; The construction of the main generator makesit possible to arrange these eXci-ter generators, which maybe at small dimensions since they-deliver practically no current; in such a manner as't'o obtain a compact assembly of small bulk. The voltage-current "characteristics of these two exciters are of'the' series" type, i; e. the potential" has a tendency to rise to the breakdown value of the gas dielectric between the electrodes;- re avoid this drawback it necessary to'provide a limi'ter consisting, for instance, in an element" connected to ground into register with which the fingers or other collectors connected with the excitation conveyors move. The fingers or collectors in such register may be at spark gap distance from the limiter element. This spark gap acts during the period of increase of potential of the conveyor and limits this potential to a predetermined value according to the adjustment of the distance between the element and the rotating finger.

Figs. 3 to 5 show a practical example of embodiment of an ignition generator for a single cylinder engine with a simultaneous double ignition, i. e. having two spark plugs between the electrodes of which sparks are initiated simultaneously.

As shown, the generator comprises an outer metal casing consisting of a cylindrical body on the ends of which are secured, in a tight manner, by means of threaded rings 22 and 22 and with interposition of gaskets 24, 24, two covers 26 and 26'. The cover 26 comprises a gland chamber 28 closed inside by a partition 30 clamped by a threaded ring 34 against a shoulder provided in the wall of the gland chamber 28, with the interposition of a gasket 32.

Upon the axis of the casing 20 is arranged a shaft 36 and 37 in two portions coupled together by coupling and rotating in bearings 33, 40, 42 and 44 supported respectively by the head wall of the gland chamber 28, the partition 30, an insulating flange 46 centered in the cover 26 and by an insulating flange 48 centered in the body 20 of the casing and prevented from rotating with respect to the cover 26' by means of studs 56 entering the corresponding holes provided in this cover. The sealing of the passage through the casing for the portion 36 of the shaft is ensured by means of a gland housed in the chamber 28 which is filled with oil, this gland consisting of two packing rings 52 and 52 held pressed, respectively, by a common spacing spring 54 in two cups 56 and 56'. The cup 56 is carried on a sleeve 58 housed, with the interposition of a gasket 60, in the bore 62 provided in the head wall of the chamber 28 for the passage of the shaft 36 through this wall. The cup 56' is carried on the wall 30. The shaft 36 carries, at its end exterior to the casing, a coupling member 64 for connection with the driving shaft normally provided on the engine for driving a coil type or a magneto type ignition distributor.

On the flanges 46 and 48 are supported two conducting inductors 66 and 66', Figs. 3, 4 and 5, secured on these flanges by means of clamping devices shown at 68 and 69. These inductors consist of cylindrical segments coaxial with the casing 20 and having an arcuate extent slightly smaller than 180 as shown in Fig. 4.

On the shaft portion 37 is keyed a cylindrical rotor 70 of insulating material comprising two portions 72 and 74 having the same diameter and separated by an annular recess in the rotor 70.

On the portion 72 of the rotor 70 are secured, by means of clamping devices 75 and 75, two conductive conveyors 76 and 76, Pig. 4, of the main generator constituted by cylindrical segments coaxial with the casing 20 and having an arcuate extent subtending substantially the same angle as the inductors 66 and 66'. These conveyors are respectively connected with two distributing fingers 7S and 78' secured in holes 80, 80 provided in the portion 72 of the rotor. These fingers are arranged for movement thereof successively during the rotation of the rotor 70 into positions opposite two fixed fingers 84 and 84' secured in the flange dti, a small interval being provided between the cooperating surfaces of the fixed fingers 84, $4 and of the movable fingers '78, '72 when they come opposite one another. The fixed fingers and 34' are respectively connected, through a stem such as 84" on which a washer 86 urged by a spring 88 is frictionally mounted, with connection elements such as 9%? arranged in insulating sleeves 92 and 92' secured pressure tight in the cover 26' by means of sealing rings 94, 94. These connecting ele- 6 ments are formed in a manner known per se for receiv ing the ends of the conductors leading to the insulated electrodes of the engine spark plugs. These spark plugs have been represented diagrammatically at 96 and 96' in Fig. 4.

On the portion 74 of the rotor 70 are secured similarly, by means of clamping devices 98 and 98' two conveyors 100 and 100' of the auxiliary excitation generator, these conveyors having, however, a length about one-third that of the conveyors 76, 76'. The conveyors 160 and 100 are respectively connected electrically with two concentric conductive rings 102 and 102 secured on the transverse end face of the portion 74 of the rotor 70, the ring 102 carrying a conductive sector 104 projecting through and with its surface flush with the surface of a ring 106 of insulating material which is wear resistant and which covers the rest of the ring 1G2, while the ring 102 carries a similar sector 164, Fig. 4, projecting through and flush with an insulating ring 106' similar to the ring 106.

In the flange 46 at a distance from the axis of the generator equal to the mean radius of the rings 102, 106 are arranged two brushes 193 and 109, Figs. 3 and 5, diametrically opposite to each other, arranged for frictionally wiping the ring 106 and the sector 104 flush therewith. Similarly, in the same flange 46 and at a distance from the axis of the generator equal to the mean radius of the rings 162', 106' are arranged two brushes 1&3 and 109 opposite to each other on the same diiameter as the brushes 108 and 109, the brushes 10S and 109' being arranged for frictionally wiping the ring 166' and the sector 1458 flush therewith. The brushes 108 and 108' are connected respectively by conductors lit) and 110' with the inductors 66 and 66, while the brushes 1G9 and 109 are connected through conductors 111 and 111 to the ground or to the casing of the generator.

The portion 72 of the rotor 78 and the conveyors 76 and 76 constitute the rotor of the main generator, while the portion 74 of the rotor 7 0 carries the conveyors 100 and 100' which are the conveyors of the respective excitation sources, the inductors 66 and 66 which are common to the two assemblies constituting the inductors of both the main generator and the two exciters.

When the rotor 70 is driven in rotation, the conveyors 1th? and 1% function as those of a conventional electrostatic generatcr with conducting conveyors. Assuming the machine is charged so that the inductors 66 and 66' respectively are at the potentials -U and +U and the conveyor tilt for instance, is in position opposite the inductor 66 at the potential -{-U, the conveyor mil then is ground ed through the sector 104 and the brush 109 and assumes a negative charge. Upon passing from the inductor 66' to the inductor 66 the potential of the conveyor 100 rises to the value U and the conveyor 1G0 then is connected with the inductor 66 through crush 19% to which it yields its charge at the potential U, thus keeping up the potential or" this inductor 66. Similarly, by the operation of the brushes 16S and 109' cooperating with the sector 104, the conveyor 1% assumes under the influence of the indoctor 66 a positive charge which it transfers through brush 168' to the inductor 66 upon rotation of the conveyor 100 to the position facing inductor 66', thus maintaining the potential of the inductor 66 at +U.

On the other hand, the assembly consisting of the inductors 66 and 66, the conveyors 76 and 76, the movable fingers 73 and 78 and the fixed fingers 84, 84 operates in a manner similar to that described in connection with Fig. l, with the difference that at each revolution of the rotor 70 sparks are produced simultaneously and respectively between the electrodes of the two spark plugs 96 and 96.

It will be understood that it is possible to design, in the same manner as in the case of Fig. 1, a generator for the ignition of six or eight cylinder engines, for instance by arranging respectively six or eight pairs of inductors. On the other hand, a device similar to that of Fig. 1 could bet used for :theesimplezignition: iof aatwoxcylinderrengine:.. byconnectingzthe twoicontaot points 8 and 8 to'onesparlo' plug; arrdzktlre two contact:rpointsrt lt" and. 83"" to: the: other:-

spark'pl-ugc In a generator like that of Fig. l in which the number ofirconveyors is. less; than that ofztheinductors; the dinien- SlOIlSOfIthfi 'assembly carr bereducedturther by inserting illBf'COIlVfiYOIS. ofi thelauxiliary exciter'generators circumferentially: between ;the conveyors of the main :generator. The di'agramwof ageneratorso designed is sh'oWnin-Fig. 6;-

ThegeneratorrepresentedinaFigr.6l comprises two pairs of-inductors 2.01, 2015. and 202; 202'. which are maintained respectively at the potentials 7U 'and"+U.. The-brushes or collector elements :208; 209, 2Hr-and2211 are-disposed adjacent the pathzof. movement; of; the: col-lectorusectors correspondingrto .onesof; the; auxiliary. exciter generators andi'the-brushesor collector elements 2%, 293", 21rd." and 211. are disposed adjacent thevpathof movement of the collector sectors corresponding: to..th'c.:0thor autiliary. e21. cites-generator.

The'auxiliary conveyors are dividedzinto threecylin.-. drical segments designated respectivelyby226, 226a, 226i). for one. of 1 the auxiliary. generators:- and: by-226, 226's, 226 12 'for the. other-one. Similarly, three conductive sec:-

tors--.cooperating.with the brusheszare provided, for one.

of the sets.- of auxiliary conveyors, that is,.sectors 227,

227aland 227b connectedrespectively with-the conveyorsegments 226, 226a and 226b, these. sectors in succession being engaged by or passing adjacent ithe'brushesZtltS; 209; 210xand 2111' in succession. Correspondingly sectors 227, 2257'a and 227'lr are connectedrespectively with the conveyorsegments 226', 226%: and .2267), .these sectors. being engagedby or passingadjacent the brushes 2101, 211 208 and 209 in succession.

Two pairs of fixed spark gaps.228,-' 228' and229,

229- are arranged relative to the directionof rotation of the conveyors so as to be passedrbythe conveyors ahead of the. brushes 208- and 210 respectively. as regards the sparklgaps 228 and 2281' and'aheadiof the brushes 2095 andZ-ll as regards the. sparkgaps 229 and 229'. These spark'gaps are arranged iIISHChZaJIIHHIWI" that the sectors 227, 227a, 2271) for the spark gaps 228 and 228- and the sectors 227, 227a and 227'b for the spark gaps 229 and'229' pass respectively= opposite the fined grounded elements of thesev sparkv gaps at a predetermined; distance,v this. distance being so selected thatthe sectorsdischarge to. the fixed" elements of the. spark gaps only when the potential of the conveyor segment connected to a sector is above predetermined potential difierence with respectto ground;

Thedevice: operates as previously described, i. e. the mainxconveyors 23.1, 231! facing the inductors 201, 201' maintained:at-.the potential U by the first exciter provide with the? respective inductors the maximum capacity C, and:the: distributingfinger or fingers (not shown in Fig. 6); connected to these main conveyors is opposite the correspondingfi'xedicollecting electrode. Two sparks takeplace simultaneously, one between said finger and this fixecLcollecting electrode and the other between the electrodes of. that spark plug towhich this fixed collecting electrode is connected. The conveyors are grounded through the circuit thusset up, since the resistance of thespark when estab1ished=is low; The potential of the conveyors. in thisposition thus becomes approximately zero.

The main conveyors 231, 231 then move from the inductors: 201; 201 to the inductors 202, 202 maintained at potential +U by the second exciter. During this-displacement, the potential V of the'main conveyors increases. as-lthe voltagesa-re notsufficient-tocause discharge across the'fixed spark gaps-228;.228 and 229; 229""corresponding. to the respective pairs of inductors during the priming period of the machine; i. e. during the time'when the potential'increases as indicated above:

The regulation impedance Z is infinite so long When the" main 8 conveyors; continuing their displacement; reach a" post tion in: which their capacities with the= corresponding? inductors .iS maXimumami' equabto C', at th'at-tiine=the; maohine operates normally and-thewwhole current de liveredl by tlfe exciter passesthrough the" spark gap- -con responding tothespark gaps 8'; 8, 8 8""; Fig. 1, thus" causing an impedance whichis in inverse proportiom proportion to-the---rotation-speed, so thatthe-producnZF of the regulation impedance by the regulating-current 'is alwaysequaltea-constant:

Considering now a" first group of auxiliary conveyor segmentsand correspondingsectors; Fig.- 6; ifth'e poten tial U of said auxiliary segments at the timewhen-the grounded element, for example; of a'- spark. gap 228" or 228and acorrespondifig-sector are opposite each other is higher than the breakdown voltage of the' dielectric; medium, the charges'flowto ground'th'rough a sparlci The potential of the successive groups of .inductors thus. willnot have the tendency to increaseexcessively.

In the. case of: application of theinvention. to the-- ignition ofan internal combustion engine, a founstrok'e engine, for instance, a simple modification offFig 6 may be;realiiedbyinserting. in between each other the auxiliary'and main conveyor members. In such a case four subdivisions in eachgroup of. conveyor' members will" be made, one conveyor member raising the corresponding inductor member to the potential +U follow? ing one. conveyor member raising-the corresponding in-. ductor to the. potential 'U.

Respectively four brushes willbe inserted in between: each other, one output brush being. followed by one brush connected to the ground, the second brush connected to. the ground 'beingfollowed by the second'outppt brush.

Respectively four fingers will'be able to cometacing said" brushes, said fingers bein connectedrespectively to four fixedcontacts connected to the voltage'limiter as hereinabove described. Thefour fixed'contacts are C011, nectedfrespectively to .theiour spark plugs ofth'eengine.

This application is a continuation offthe applicationofi Noel'Felici and'MarcelPoint, Serial'No. 258,348, filed' November 27, .1951; now abandoned.

We claim:

11 An. electrostatic generator comprising. apair. of inductor members in spaced relation. to. each other, a. conveyor. member, said conveyor memher and]. said pair] of inductor. members being sup.- ported. for. relative movement thereof. with respect to. each other. into. and out of. inductive relation. of; said. conveyor member. to said. inductor. members .insuccession, means. for maintaining said.ir1ductor. members at different potentials-,, charge. conducting. means, connected to said. conveyor; member for conducting .a charge; carried; bysaidconveyor member,.said charge conducting means and said pair of inductor members being supp ortedifor.

relativemovement thereof with respect to. each other concomitantlywithsaidrelativemovement of said conveyor; member. and saidpair of inductor members with respect;to. eachother, and charge transfer elementsdisposed inspaced relation to each other along and adjacent the path of. said.relative'm.ovement of said-charge con.- ducting means and said pair. of inductor members with respectto eachotherso that said.charge conducting means becomesdisposed at spark gap distancefrom said charge transfer elements in succession concomitantly with said: movement of said conveyor member and said inductor members into and out of inductive relationto each other.

2. An electrostatic generator as defined: in claim 1 in which said charge transferelements are disposed in positions'such that said charge conducting means becomes disposed at sparkgap distance from said transfer elements in succession at predetermined positions of saidconveyor member'respectively in relation to; said inductor members.

31 An electrostatic generator as defined in claim 1,

in which said charge transfer elements are disposed so as to be in spark gap relation to said charge conducting means in the positions respectively of said conveyor member in which said conveyor member is substantially in full inductive relation to the respective inductor members.

4. An electrostatic generator as defined in claim 1, in which said charge transfer elements are disposed so as to be in said spark gap relation to said charge conducting means in positions of said conveyor member in which said conveyor member is moving into inductive relation to the respective inductor members.

5. An electrostatic generator as defined in claim 1, in which said charge transfer elements are disposed so as to be in said spark gap relation to said charge conducting means in positions of said conveyor member in which said member is moving out of inductive relation to the respective inductor members.

6. An electrostatic generator as defined in claim 1, which comprises means for confining in dielectric rela tion to said inductor and conveyor members and to said charge conducting means and said charge transfer elements a gaseous dielectric medium under super-atmospheric pressure.

7. An electrostatic generator comprising a pair of inductor members in spaced relation to each other, a conveyor member, said pair of inductor members and said conveyor member being supported for movement thereof relative to each other into and out of inductive relation of said conveyor member to said inductor members in succession, means for maintaining said inductor members at different predetermined potentials, charge conducting means connected to said conveyor member for conducting a charge carried by said conveyor member and supported for movement of said charge conducting means and said pair of inductor members relative to each other concomitantly with said relative movement of said conveyor member and said pair of inductor members with respect to each other, and charge transfer elements respectively associated with said inductor members and disposed in spaced relation to each other along and adjacent the path of said relative movement of said charge conducting means and said pair of inductor members with respect to each other so that said charge conducting means becomes disposed at spark gap distance from said charge transfer elements in succession in a predetermined relation to the movement of said conveyor member and said inductor members into and out of inductive relation to each other.

8. An electrostatic generator comprising a pair of inductor members in spaced relation to each other, a pair of conveyor members, said pair of conveyor members and said pair of inductor members being supported for relative movement of said pairs with respect to each other into and out of inductive relation of said conveyor members in succession to said inductor members in succession, means for maintaining said inductor members of said pair of inductors members at difierent potentials, charge conducting means connected to said conveyor members for conducting the charges carried by said conveyor members, said charge conducting means and said pair of inductor members being supported for relative movement of said charge conducting means and said pair of inductor members with respect to each other concomitantly with said relative movement of said pair of conveyor members and said pair of inductor members with respect to each other, and charge transfer elements disposed in spaced relation to each other along and adjacent the path of relative movement of said charge conducting means and said pair of inductor members with respect to each other so that said charge conducting means becomes disposed at spark gap distance from said charge transfer elements in succession concomitantly with said movement of said conveyor members and said inductor members into and out of inductive relation to each other.

9. An electrostatic generator as defined in claim 8 which comprises means for connecting a charge transfer element at a given position along said path relative to the positions of said inductor members to a potential intermediate between said potentials of said inductor members.

10. An electrostatic generator comprising a pair of inductor members, said inductor members of said pair being disposed in circumferentially spaced relation to each other about an axis of rotation, a pair of conveyor members supported in circumferentially spaced relation to each other about said axis of rotation, said pair of conveyor members and said pair of inductor members being supported for relative rotational movement of said pairs about said axis with respect to each other into and out of inductive relation of said conveyor members in succession to said inductor members in succession, means for maintaining said inductor members of said pair at different potentials, charge conducting means connected to said conveyor members for conducting the charges carried by said conveyor members, said charge conducting means and said pair of inductor members being sup ported for relative rotational movement of said charge conducting means and said pair of inductor members with respect to each other concomitantly with said relative rotational movement of said pair of conveyor members and said pair of inductor members with respect to each other, and charge transfer elements disposed in circumferentially spaced relation to each other about said axis along and adjacent said path of relative rotational movement of said charge conducting means and said pair of inductor members with respect to each other so that said charge conducting means becomes disposed at spark gap distance from said charge transfer elements in succession in predetermined positions of said conveyor members relative to said inductor members in said movement of said conveyor members and said inductor members into and out of inductive relation to each other.

11. An electrostatic generator comprising at least two pairs of inductor members, the inductor members of each pair being disposed in angularly spaced relation to each other peripherally about an axis of rotation and in interspersed relation to the respective inductor members of another pair, at least two conveyor members supported in angularly spaced relation to each other about said axis substantially the same as the angular spacing between the inductor members of each pair of said inductor members and for rotation about said axis, means for maintaining the inductor members of alternate pairs at two different predetermined potentials, charge conducting means respectively connected to said conveyor members for conducting the charges carried by said conveyor members and supported in angularly spaced relation to each other about said axis similar to the angular spacing of said conveyor members and for rotation about said axis with said conveyor members, charge transfer elements respectively associated with said inductor members of said pairs and disposed in angularly spaced relation about said axis corresponding to the angular spacing of said inductor members of each pair and adjacent the path of movement of said charge conducting means so that said charge conducting means in said rotational movement thereof with the respective conveyor members with respect to said inductor members become disposed in succession at spark gap distance from said charge transfer elements in succession, and means for connecting said charge transfer elements to a potential intermediate between said potentials of said inductor members.

12. An electrostatic generator as defined in claim 11, in which said intermediate potential is ground potential and'said different predetermined potentials are symmetrical with respect to ground potential.

13. An electrostatic generator for an ignition system having a plurality of spark plugs, given electrodes of said plugs being connected in common to a reference potential, said generator comprising a pair of inductor members in spacedirelation' to each other, a. conveyor. member, said pair'ofinducton members andsaid conveypr member. beingsupportedfor movement thereof "relative to each other'into andout of inductive relation ofsaid'conveyor member to said inductor members in succession, means for maintaining saidinductor members at'diflerent predetermined potentials, saidreference. potenti'al'being intermediate-between said predetermined potentials, charge conducting means connected to said conveyor member for conducting a charge, carried "by said" conveyor memher; said charge conducting-meansand" said pair of inductormembers being supported for relative' movement tbereofi 'with-respect to eachother'concomitantly with said rel-at-i-ve== movement of saidconveyor member and said pair of inductor-=members Withrespcct'to each other; and chargetransfer-elements disposedid spaced relation to eachot-her-irr a -predetermined relation to thespacing of" said' inductor members and-along 'and adjacent the path of relative movement of said charge conducting means and said pair of inductor members with respect K to each otherisoathatlsaid charge conducting-means becomes disposetiuin spark: gaprelation to said -charge-transfer' elements: in succession; said charge transfer elements beingdisposedzso as .to be in saidspark gap relation to said chargenconductingmeans in the positions respectively of said conveyortmember in which said COI1VYOPIDH1bf lS substantially; in fulliindnctive relation to. the. respective inductorrmembers for discharge through said :sparkrplugs WhEIISflldr charge. transfer elements respectively areconnected tothetother electrodesof the respectivespark plugs of saidignition system.

1.4.: Anelectrostatic generator. comprisinganinductor: member, a conveyor member, said ginductor member and said, conveyor member being supported-for-movement: thereofrelative to each other into and outof inductive; relation of. said conveyor member. with respect tosaid: inductor member, means, for maintaining said; inductor at.a.givenpotential,, said conveyor membenbeingscomposed of-a, plurality of conveyor segments spacedin-Ihedirection=along the path of relative movement of-saidconveyonmember and said inductor member, charge-cone ducting. sectors respectively connected to said'conveyor member. segments for conducting thecharges carried. by said segments andsupported in spaced relation in the di-- rection parallel to saidupath of relative..movementofsaid; conveyorand inductor members for relative: movement of said sectors' and said inductor member with respect toeach. other concomitantly-With said relative movement .of said. conveyonand saidinductormember with {respect toeach other; and. a charge. transfer element disposed adjacent the. .path -of,relative movement of said charge. conducting sectors and said'tinductor member with respect to-.each. other southat the. respective sectors; become disposedinsuccessionrin charge transferring relation to saidscharg er. transfer. element inaposi-tionof the. respectivetsegments inwhich. such segmentais in apredetermined inductive. relation torsaidsinductor member.-

15. An. electrostatic. generator as .defineduinv claim l4: which-comprises an auxiliary charge transfe'relement disposedand adjacent said path of relative movementofsaid. chargeconducting.sectors and said inductor member with. respect. 5 to each other so. that the respective sectors be-. comedisposed, insuccessionat sparkgapdistance from. said auxiliary ttransferrelement .in..-thet.posi ti0n-..0fthe seg;

mentconnected-toihe respective sector.in-..Which..such

segment is. moving into inductive 1 relation to can inductor iember, saidauxiliarytransfer element..being connectedt to a potentialqdetermining in relation ;to..-a-p redetermined potentiah of said conveyor segment in said. positionzth'ereof a potential difference 1; corresponding; to ,J discharges across said spark gap.

16;; An electrostatic generator:comprisingaatileasttwo inductor 1' members,.. a; conveyormemb'en; said-.2 inductor members sandzsaid :conveyor member :beingasupported :Ifon monement dhereonrrelativ'e tOceaCh: other: time -and::out 0f? Cal 12.. inductive, relation :of said conveyor member-withrespect. to; said inductor membersin succession; means formaintaining saidjinductor. membersat different predetermined,- potentials, said'conveyor. member, beingcomposed of a1 plurality of conveyor. segments spaced in. the: direction along the path of'relative movement of. said conveyormember and. said inductor members, charge conducting. sectors respectively connected'to 'saidconveyor member segments for conducting the charges carriediby saidsegments and supported in spacedrelation in the direction parallel to,said path oflrelative movement. of saidconveyor member and'saidinductor members forrelative. movement With said segmentsiof said. sectors and saidinductormembers ,with respect toeach' other, charge trans.- fer elements respectively. associated: with said'inductor. members and disposed in spacedrelation similar to -the spacing of said inductor members adjacent the. path of relative movement of saidcharge conducting-.sectorsand. said inductor members with respect to eachother. so that said sectors in said relative movement thereof with said. conveyor. segments .With respectto .saidinductor members become disposed in succession in charge transferring .re lation to .said charge.transfer-elementsin-succession; and means for connecting thechargetransfer.elementassoci:

' ated with agiven inductormember to apotentialdntermediate. between saidpredetermined potentials of said in ductormembers to charge saidconveyor.segmentsatsaid intermediate. potential when said.conveyorsegmentszare in inductive relation :to said. given inductor-member.

17. An electrostatic generator as defined-.inclaim. 16 which comprises means for. connecting theother charge transfer element/associated. with .the other inductor. memher to saidiother inductormember for transfer of charge therebetween.-

18. An electrostatic generator; astxdefinedinclaim- 16. which comprises at least oneadditional conveyor. member; said,additional conveyor memberiand saidinduotor'mem-n bersbeing supported for movement thereof relativetoi each other into and out of inductive. relationof said ad.- ditionaliconveyormember withrespeet to..said inductormembers. insuccession, said additional conveyor member; being composed of a plurality of conveyor segments spaced inthe direction along the path of relative. move-- ment of said additional conveyor member and said in: ductormembers; a plurality of additional. charge conducting sectors respectively. connected .-to said: additional con-- veyor member segments and supported inspaced relation. in the direction parallel to the path ofgrelative movement ofsaid additional conveyor member. and. said inductor.

' members forrelative. movement ofsaidadditionalsectors.

andsaid inductor members withrespectito eachtother, additional charge transfer elements 1 respectively. ass0ci-.- ated .with said inductor mCIIIbEI'SAIIdidiSROSCd inspaced relation similar. to the spacingof said inductor. members and. adjacent the path of relative movement of said. charge conducting .sectors of said. additional-.conveyor member With respect to said inductor members so.-that.said.additio-nal sectors in said relative.movementthereofwith said. additional conveyor segments with respect .to .said. induc 'tor; members-.become-= disposed. 'in succession. in charge.

transferring; relatiom to said; additional charge transfer elementsin succession,- andmeanstfor connecting the ad-J ditional charge. transfer. element associated with aselected inductor: member. to; a. potential intermediate between. said predetermined.potentials of .saidinductormem:

bers to. charge saidadditional .conveyorsegmentsxat said intermediate.- p otentialwhen said additional ;conveyor.-'seg; ments arein.inductivevrelationto said selected inductor member, the. otherz additional. charge.- transfer element associated with a second inductor member rbeing cflnnected to .saidsecond inductor. member fortransfer of-tcharge: therebetween.

l9. Ail-electrostatic generator. as definedrin-claimt. 16. which comprises a charge transfer element diSPOSCd'zfOl'r- ,wardly in the direction.-of movementrof: said. conveyor 13 member relative to said inductor members from said charge transfer element associated with said given inductor member so that said sectors in said relative movement thereof with said conveyor segments With respect to said inductor members become disposed in succession at spark gap distance from said forwardly disposed charge transfer element for spark gap discharge thereto of charges carried by said conveyor at a potential in excess of a predetermined potential.

20. An electrostatic generator comprising a pair of inducto-r members in spaced relation to each other, a pair of conveyor members, said pair of conveyor members and said pair of inductor members being supported for relative movement of said pairs With respect to each other into and out of inductive relation of said conveyor members in succession to said inductor members in succession, means for maintaining said inductor members of said pair of inductor members at difierent potentials, charge conducting means connected to said conveyor members for conducting the charges carried by said conveyor members, said charge conducting means and said pair of inductor members being supported for relative movement of said charge conducting means and said pair of inductor members with respect to each other concomitantly with said relative movement of said pair of conveyor members and said pair of inductor members with respect to each other, and charge transfer elements disposed in spaced relation to each other along and adjacent the path of relative movement of said charge conducting means and said pair of inductor members With respect to each other, said charge conducting means being disposed at spark gap distance from said charge transfer elements to effect sparking therebetween concomitantly with said movement of said conveyor members and said inductor members into and out of inductive relation to each other in succession.

References Cited in the file of this patent UNITED STATES PATENTS Felici Nov. 14, 1950 Felici Mar. 25, 1952 

